The World Health Organization (WHO) recommends that unless breastmilk substitutes are acceptable, feasible, affordable, sustainable, and safe, HIV positive mothers in developing countries should exclusively breastfeed for the first 6 mos. Postpartum and wean thereafter when a nutritionally adequate and safe diet is available. The weaning period can be high risk for such infants due to lack of fully adequate replacement feeds resulting in malnutrition and susceptibility to diarrheal and respiratory illness from loss of breastmilk's immune protection. In addition, risk of HIV transmission is increased if a mother breastfeeds during weaning due to higher breastmilk viral load during this time. Appropriate feeding alternatives during and after weaning are urgently needed. Although listed by WHO as a breastfeeding modification, heat treatment has not been fully explored. Our data demonstrate that Flash-heat (FH), a simple home pasteurization method, is capable of inactivating HIV in infected breastmilk while maintaining most vitamins and immunoglobulins. This suggests FHed breastmilk could be an infant feeding option during and after weaning to decrease risks of introducing complementary foods. This study will investigate use of enhanced peer-based infant feeding counseling to improve exclusive breastfeeding (EBF) durations and the feasibility of FHing breastmilk. HIV-infected mothers who plan to breastfeed will be recruited antenatally at hospitals in Tanzania and provided enhanced counseling to EBF. Trained community health workers (CHWs) will make weekly home visits to support mothers and collect infant feeding and breast health data. Prior to introduction of complementary foods, FH will be discussed as an option for during and after transition. Mothers who choose FH will be provided home-based support and followed for up to 3 mos. from weaning. This feasibility and pilot efficacy study of FHing breastmilk will be used to guide a full-scale efficacy trial. Specific aims include to: 1) Determine the impact of enhanced home-based support on EBF duration. Given clinical staffing shortages in Tanzania, CHWs could provide support needed to EBF longer. 2) Determine uptake of the FH method and protocol adherence by mothers in their homes. With enhanced training and support, mothers may choose to FH milk, suggesting it could be practical for infant feeding. 3) Determine safety of FHed breastmilk in a field setting. Milk samples will be collected and assayed for HIV inactivation and bacterial counts to ensure method safety. 4) To pilot an efficacy trial of FH to improve infant health outcomes. Clinic assistants will monitor infant growth and morbidity during home visits twice monthly. Feasibility data are necessary to properly plan an efficacy trial, in turn necessary so that counselors can better inform mothers of risks and benefits of different feeding options in the future. Project Relevance [unreadable] [unreadable] The World Health Organization recommends that HIV positive mothers in developing countries exclusively breastfeed for six months then stop once safe and nutritious foods are available, but this weaning period can be a risky time for the baby because of lack of complete nutrition, the chance of getting sick from contaminated foods and even an increased possibility of getting HIV if the mother breastfeeds. Heating expressed breastmilk can kill HIV and keep milk's protective qualities, so it could be a safe and healthy way for a mother to feed her baby during this risky time. In this study, we will see if women from the community who visit HIV positive mothers in their homes could increase the mean duration of exclusive breastfeeding and if it is feasible for mothers to express and heat their milk after they introduce other foods. [unreadable] [unreadable] [unreadable]